1. Field of the Invention
The present invention relates to motion picture reels upon which motion picture film is wound and unwound as it is passed through a motion picture projector for presentation of a motion picture to a viewing audience.
2. Description of the Prior Art
Motion pictures are created by a series of photographs taken rapidly in sequence and arranged on a length of film. The film is wound on a motion picture reel and fed through a motion picture projector at a predetermined speed that is rapid enough to produce the illusion of actual movement of the figures in the sequence of photographs as the photographs are projected on the screen. The film is wound on the motion picture reel in a helical fashion about a hub that is fixed between a pair of much larger, narrow, planar retaining members. As film is advanced through the projector it is pulled off of one reel, advanced through the projector, and wound on a take-up reel. At the conclusion of presentation of the motion picture, the film is rewound back onto the original reel from which it was drawn during the presentation process.
In the motion picture industry, motion pictures are timed for release at a great number of locations during and immediately following very expensive promotional advertising campaigns. To maximize the number of viewers in the audiences, a great number of copies of a motion picture are created and are then distributed concurrently to numerous different movie theaters at the height of interest created by the advertising campaign. This distribution technique necessitates the creation of a great number of copies of each motion picture at the time of distribution. Each copy requires a separate, dedicated motion picture film reel.
During and immediately following the period of advertising promotion, a motion picture is widely exhibited at many different locations at the same time. Following the promotional period, however, the multitude of copies of the motion picture film produced and previously required are no longer necessary, and indeed, constitute a problem.
It is highly desirable for excess copies of motion picture films to be destroyed rather than stored. Films to be stored for later use must be maintained under hermetically sealed conditions so as to avoid degradation of the film copy. While certainly a limited number of copies of the film are preserved for possible recirculation and for use as masters for the possible reproduction of additional copies at a future time, the great majority of the copies of motion pictures produced are destroyed following a limited period of wide-spread exhibition in movie theaters.
There are several reasons for destroying the many copies of a motion picture film that are no longer required after the initial period following release of the film. The expense of storing the very large number of copies which were once necessary in order to exhibit the motion picture at a multitude of different movie theaters cannot be justified. The cost of protection and storage of each copy of the motion picture film far outweighs the incremental cost of producing another motion picture copy should another copy be required. Moreover, when copies of motion picture films are stored they must be safeguarded against misappropriation. As a consequence, destruction of the excess number of copies of a motion picture film following release and circulation is a highly desirable alternative to storage.
Originally, motion picture film reels were made of metal. At the time of destruction the motion picture film was drawn off of such a reel and cut into small, unusable pieces for disposal. However, this was a very time consuming, and therefore expensive process.
Because of the lengthy time required to unwind a copy of a motion picture film for destruction, quicker destruction methods were devised. One method was to construct the reel upon which the film was wound of a plastic material that could be broken in order to retrieve the film for destruction without unwinding it when the copy of the film became redundant. As a consequence, the film did not have to be pulled lengthwise off of the reel by rotating the reel for a lengthy period of time, but instead could be pulled transversely off of the hub and destroyed without unwinding it.
However, since the film reel had to be made strong enough to withstand repeated transport and use and reuse during exhibition of the motion picture, the reel had to be constructed in a reasonably sturdy manner. As a result, smashing of the reel was laborious and also at times difficult. Moreover, the cost of replacing these reels for use with other motion picture films was considerable.
More recently, motion picture reels have been produced which are formed of component members that are releaseably attached to each other. These conventional members include a pair of circular retaining plates and a much smaller central hub which can be releaseably fastened together. Originally the two retaining portions of the reel were screwed together. When the copy of the motion picture film wound thereon was no longer desired, the components of the reel were unscrewed from each other to provide complete access to the film wound on the central hub. However, the parts of this type of reel could accidentally become unscrewed during the time the film was in distribution.
A further type of motion picture film reel is now being produced in which the two halves of the motion picture reel include interlocking fingers at the hub that flex resiliently to interlock with a corresponding structure projecting from the other half of the reel. These two retaining members each include a metal insert into which a key is inserted. When the key is rotated, the fingers are deflected from engagement with the other portion of the reel, so that the two reel portions can be pulled apart. Each of the reel halves also includes either portions of an integrally formed hub portion upon which the film is wound or a hub insert. In either case a key is necessary to work within the metal insert so as to detach the reel halves from each other.
With this conventional design, the metal insert becomes a problem in ultimately disposing of such reels once they have outlived their useful lives. The metal insert cannot be readily separated from the plastic. Therefore, recycling of the plastic portion of the reel, which represents by far the greater portion of the structure of the reel, becomes very difficult since the metal insert must first be removed.
A significant advance in the construction of motion picture film reels was achieved in prior U.S. Pat. No. 5,676,332 issued Oct. 14, 1997. That patent describes a completely recyclable motion picture film reel, formed completely of plastic and having component parts that are releaseably attached together. In the structure of the device of that prior patent a pair of side retainers each formed of a generally flat, planar member are provided with a pair of resilient prongs defining catches thereon. These prongs are diametrically opposed to each other and extend through the hollow core of a hub so that the catches at the ends of the prongs releaseably engage the far side of the hub. The prongs of each of the side retainers are angularly displaced ninety degrees from the prongs of each other side retainer and pass through channels defined in the base of the other side retainer so that the side retainers are immobilized relative to each other as well as relative to the hub. However, for larger reels there is a tendency for the prongs to break off since they can be subjected to considerable stress if torsional forces are exerted on the side retainers.
In U.S. Pat. No. 5,775,634 issued Jul. 7, 1998 this problem was addressed and solved by providing the hub-engaging region with a pair of rigid posts having catches formed thereon that engage circular openings in the web of the motion picture reel hub. While this provides a much sturdier arrangement, one further problem that has persisted has been the tendency for a certain amount of play to exist in the angular alignment of the laterally confining retaining members. That is, the retaining members on the opposing sides of the reel can be twisted slightly relative to each other, thereby causing stress on the posts that project from the retaining members to engage the openings in the hub. Such stress can cause the posts to break.